Hey guys I keep having an error on my phone. It happened after I tried to upgrade to Windows Mobile 10. After the phone stays on for 5 mintutes it says sim error, sim is invalid. But the sim card works til five or so minutes. Tried a different sim card, same issue. Can anyone please help me out, it's not even my phone I just tried upgrading someone's phone for them following Microsoft's steps... No good deed goes unpunished
ATT Windows Mobile phone 640 LTE keeps saying sim erro |
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Jul 12, 2017 01:23 PM
(This post was last modified: Jul 12, 2017 01:27 PM by Dr.Schere.)
First you can try to make a hard reset and have a look at the sim security
If the problem still remains you can try to downgrade to an earlier firmware |
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